A traditional door hinge having a damping function usually comprises a housing, a first rotating shaft, a U-shaped rotating shaft, a hinge cup, a connector, a linkage member, a pusher and a damping cylinder. The piston rod of the damping cylinder is rotationally connected to the pusher, and the pusher is connected to the linkage member. Such a design has a very complicated structure. In particular, during use, the pusher is pulled by the piston rod of the cylinder to achieve a damping effect. In such a configuration, the piston rod fails to move in the axial direction, resulting in a greater friction between the piston rod and the sealing ring of the cylinder. Consequently, oil leakage can easily occur after a prolonged use, leading to problems such as hinge failure, difficult maintenance and low precision of the door hinge, resulting in a shortened life span.